#!/usr/bin/perl
use warnings;
use strict;

print "Enter a number between 0 to 256 : ";
my $dec = <STDIN>;
my @bits;

$bits[7] = ($dec & 128) <=> 0;
$bits[6] = ($dec & 64) <=> 0;
$bits[5] = ($dec & 32) <=> 0;
$bits[4] = ($dec & 16) <=> 0;
$bits[3] = ($dec & 8) <=> 0;
$bits[2] = ($dec & 4) <=> 0;
$bits[1] = ($dec & 2) <=> 0;
$bits[0] = ($dec & 1) <=> 0;
printf "The entered decimal number in binary is : %s\n", join '', reverse @bits;